Vent feature protection brackets for electrified vehicle traction battery packs

This disclosure relates generally to electrified vehicles, and more particularly to protection brackets for shielding traction battery pack vent features from debris impingement.

Some electrified vehicles include a traction battery pack packaged at external, underbody locations of the vehicle. At such a mounting location, portions of the traction battery pack may be susceptible to debris impingement.

A traction battery pack according to an exemplary aspect of the present disclosure includes, among other things, an outer enclosure assembly, a vent feature mounted to a portion of the outer enclosure assembly, and a protection bracket arranged relative to the vent feature and configured to shield the vent feature from debris impingement.

In a further non-limiting embodiment of the foregoing traction battery pack, the portion is part of a cover of the outer enclosure assembly.

In a further non-limiting embodiment of either of the foregoing traction battery packs, the portion is part of a tray of the outer enclosure assembly.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the protection bracket is secured to the portion of the outer enclosure assembly by a two-sided adhesive tape.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the protection bracket includes a polymeric body having a front surface that faces in a direction away from the vent feature and a rear surface that faces in a direction toward the vent feature.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the polymeric body is made of polypropylene.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the polymeric body includes a melting point that is less than a temperature of a battery vent byproduct of the traction battery pack.

In a further non-limiting embodiment of any of the foregoing traction battery packs, a plurality of openings is formed through the polymeric body.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the plurality of openings is arranged in a mesh pattern.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the mesh pattern includes a first cross-sectional area that is about equivalent to a second cross-sectional area of an opening of the outer enclosure assembly that is covered by the vent feature.

An electrified vehicle according to another exemplary aspect of the present disclosure includes, among other things, a frame member, a traction battery pack including an outer enclosure assembly, a mounting linkage arranged to mount the traction battery pack relative to the frame member, a vent feature secured to the outer enclosure assembly, and a protection bracket arranged over the vent feature and configured to shield the vent feature from debris impingement.

In a further non-limiting embodiment of the foregoing electrified vehicle, an isolator is arranged between the mounting linkage and the frame member.

In a further non-limiting embodiment of either of the foregoing electrified vehicles, the protection bracket is secured to a cover of the outer enclosure assembly by a two-sided adhesive tape.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, the protection bracket includes a polymeric body having a front surface that faces away from the outer enclosure assembly and a rear surface that faces toward the outer enclosure assembly.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, a maximum forced deflection of the polymeric body is about equal to an amount of relative movement permitted between the traction battery pack and the frame member.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, the front surface includes at least one clipped corner and at least one impression.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, the rear surface includes at least one mounting pad.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, the polymeric body includes a plurality of openings formed therethrough.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, the plurality of openings is arranged in a mesh pattern.

In a further non-limiting embodiment of any of the foregoing electrified vehicles, the polymeric body is made of polypropylene.

The embodiments, examples, and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible.

The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.

This disclosure details protection brackets for shielding vent features of electrified vehicle traction battery packs. An exemplary protection bracket may be made of a polymeric material and is designed to shield the vent feature from debris impingement. The protection bracket may include features such as a mesh venting pattern and a melting point that is lower than the temperature of battery vent byproducts that may be released during battery thermal events of the traction battery pack. These and other features are discussed in greater detail in the following paragraphs of this detailed description.

schematically illustrates an electrified vehicle. The electrified vehiclemay include any type of electrified powertrain. In an embodiment, the electrified vehicleis a battery electric vehicle (BEV). However, the concepts described herein are not limited to BEVs and could extend to other electrified vehicles, including, but not limited to, hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEV's), fuel cell vehicles, etc. Therefore, although not specifically shown in this embodiment, the electrified vehiclecould be equipped with an internal combustion engine that can be employed either alone or in combination with other power sources to propel the electrified vehicle.

In an embodiment, the electrified vehicleis a pickup truck. However, the electrified vehiclecould alternatively be a car, a van, a sport utility vehicle, or any other vehicle configuration. Although a specific component relationship is illustrated in the figures of this disclosure, the illustrations are not intended to limit this disclosure. The placement and orientation of the various components of the electrified vehicleare shown schematically and could vary within the scope of this disclosure. In addition, the various figures accompanying this disclosure are not necessarily drawn to scale, and some features may be exaggerated or minimized to emphasize certain details of a particular component or system.

In the illustrated embodiment, the electrified vehicleis a full electric vehicle propelled solely through electric power, such as by one or more electric machines, without any assistance from an internal combustion engine. The electric machinemay operate as an electric motor, an electric generator, or both. The electric machinereceives electrical power and provides a rotational output torque to one or more drive wheels.

A voltage busmay electrically couple the electric machineto a traction battery pack. The traction battery packis an exemplary electrified vehicle battery. The traction battery packmay be a high voltage traction battery pack that includes a plurality of battery arrays(i.e., battery assemblies or groupings of rechargeable battery cells) capable of outputting electrical power to power the electric machineand/or other electrical loads of the electrified vehicle. Other types of energy storage devices and/or output devices could alternatively or additionally be used to electrically power the electrified vehicle.

The traction battery packmay be mounted at various locations of the electrified vehicle. In an embodiment, the electrified vehicleincludes a passenger cabinand a cargo space(e.g., a truck bed) located to the rear of the passenger cabin. A floor panmay separate the passenger cabinfrom a vehicle frame, which generally establishes an underbodyof the electrified vehicle. The traction battery packmay be suspended from or otherwise mounted relative to the vehicle framesuch that it is remote from both the passenger cabinand the cargo space. The traction battery packtherefore does not occupy space that would otherwise be available for carrying passengers or cargo.

Referring now to, the traction battery packmay include an outer enclosure assemblyfor housing the battery arraysand other battery internal components (e.g., electronics, wiring, etc.) of the traction battery pack. The outer enclosure assemblymay be sealed enclosure having any size, shape, and configuration and may, in an exemplary embodiment, include a trayand a cover.

In an embodiment, the outer enclosure assemblyis a metallic-based component. For example, the trayand the covercould be constructed out of aluminum or steel.

In another embodiment, the outer enclosure assemblyis a polymer-based component. For example, the trayand the covercould be constructed (e.g., molded) of expanded polymer-based materials, solid polymer-based materials, or a combination of such materials. Exemplary expanded polymer-based materials can include, but are not limited to, expanded polypropylene, expanded polystyrene, and expanded polyethylene. Exemplary solid polymer-based materials can include, but are not limited to, sheet moulding compounds (e.g., glass-fiber reinforced polyester), polypropylene, and polyamine.

In yet another embodiment, the outer enclosure assemblycould be constructed of both metallic-based and polymer-based components. For example, the traycould be a metallic-based component, and the covercould be a polymer-based component. Other configurations are also contemplated within the scope of this disclosure.

The outer enclosure assemblymay further include a vent feature, which may sometimes be referred to as a pressure equalization feature. The vent featuremay be a vent patch, filter, or some other porous membrane that may be disposed within a wall of the outer enclosure assemblyfor providing pressure equalization between the interior of the traction battery packand atmosphere. The vent featuremay allow gases (e.g., air) to flow in and out of the outer enclosure assemblywhile preventing moisture, particle contaminants, etc. from entering the interior of the traction battery pack.

The vent featuremay be secured to a portion of the outer enclosure assembly. In an embodiment, the vent featureis secured to the coverof the outer enclosure assembly. In another embodiment, the vent featureis secured to the trayof the outer enclosure assembly(see). However, the specific mounting location of the vent featureis not intended to limit this disclosure.

, with continued reference to, schematically illustrates the traction battery packmounted relative to the vehicle frameat the underbody. The vehicle frame(sometimes referred to simply as a “frame”) is the main supporting structure of the electrified vehicle, to which various components are attached, either directly or indirectly. The vehicle framemay include a unibody construction, in which the chassis and body of the electrified vehicleare integrated into one another, or may be part of a body-on-frame construction. The vehicle framemay be made of a metallic material, such as steel, carbon steel, or an aluminum alloy, as non-limiting examples.

The vehicle frameincludes a plurality of frame members, which may be configured as longitudinally or horizontally extending rails/beams.shows one such frame member, however, the vehicle framecould include additional frame members.

One or more mounting linkagesmay be used to mount the traction battery packto the frame member. The mounting linkagemay be welded, bolted, or both welded and bolted to the traction battery packand to the frame member. The total number and configuration of the mounting linkagesused to mount the traction battery packrelative to the underbodymay vary per vehicle design and is therefore not intended to limit this disclosure. In the mounted position, a gap G may extend between the traction battery packand the frame member. It should be recognized that the gap G is not shown to scale and has been exaggerated to better illustrate certain features of this disclosure.

An isolatormay optionally be secured between the frame memberand the mounting linkage. The isolator, which may be referred to as a bushing, is configured to dampen energy that is transmitted to the vehicle frameand may thus acts as a point of isolation for isolating the traction battery packfrom vibrations and other loads that may act on the vehicle frame.

The isolatormay permit a relatively small amount of movement to occur between the traction battery packand the vehicle frame. For example, the isolatormay allow the traction battery packto move in multiple degrees of freedom relative to the frame memberin order to create a modal misalignment between the traction battery packand the vehicle frame. The modal misalignment can be effective to isolate the traction battery packfrom at least some of the loads that may act on the vehicle frame.

Due at least in part to the mounting location at the underbody, the size of the gap G, and/or the relative motion that may occur between the traction battery packand the frame memberduring vehicle operation, debris D (e.g., a rock, stone, etc.) could become lodged or otherwise captured within the gap G and impinge on the traction battery pack, thereby applying an impingement load against the outer enclosure assembly. In some instances, the impingement load could be applied in the vicinity of the vent featureor could even pierce the vent feature, thereby undermining its functionality. This disclosure is therefore directed to protection brackets designed for shielding the vent featurefrom debris impingement.

illustrate an exemplary protection bracketfor shielding the vent featureof the outer enclosure assemblyof the traction battery packfrom debris impingement that could occur during operation of the electrified vehicle. The protection bracketmay be positioned over the vent featureand may be secured to a surfaceof the outer enclosure assembly. The surfacemay be part of the trayor the cover, depending on the mounting location of the vent feature. When mounted to the surface, the protection bracketsubstantially covers the vent featurefor directing debris away from the vent featurein debris impingement scenarios.

In an embodiment, the protection bracketis secured to the surfaceof the outer enclosure assemblyusing one or more sections of two-sided adhesive tape(see, e.g.,). In another embodiment, the protection bracketis secured to the surfaceusing one or more mechanical fasteners, such as bolts or screws, for example (see, e.g.,).

The protection bracketmay include a polymeric bodyhaving a front surface(see) and a rear surface(see). When the protection bracketis mounted to the outer enclosure assembly, the front surfaceof the polymeric bodyfaces in a direction away from the surfaceof the outer enclosure assembly, and the rear surfaceof the polymeric bodyfaces in a direction toward and interfaces with the surfaceof the outer enclosure assembly.

In an embodiment, a melting point of the polymeric bodyis less than a temperature of battery vent byproducts V (see) that may be vented by the traction battery packduring battery thermal events (e.g., overcharging, overdischarging, overheating, etc.). The protection brackettherefore cannot block the battery vent byproducts V from escaping the outer enclosure assemblyduring thermal runaway events.

In an embodiment, the polymeric bodyof the protection bracketis made of polypropylene. However, other polymeric materials could alternatively be utilized to construct the protection bracket. The polymeric bodymay be made of a different material compared to both the vent featureand the surfaceof the outer enclosure assembly.

At least a portion of the polymeric body, such as the front surface, for example, may include a first color C. The first color Cmay be a different color from a second color Cof the vent featureor a third color Cof the surfaceof the outer enclosure assembly. In an embodiment, the first color C, the second color C, and the third color Care each different colors for simplifying assembly of the traction battery packduring manufacturing.

A plurality of openingsmay be formed through the polymeric bodyof the protection bracket. The openingsmay extend completely through the polymeric bodyand therefore open through both the front surfaceand the rear surface.

The openingsmay be arranged in a mesh pattern P. The mesh pattern P is configured to enable the vent featureto continue to provide its pressure equalization functionality even though partially covered by the protection bracket. The mesh pattern P may further establish a cross-sectional area that is about equivalent to a cross-sectional area of an opening(see) of the outer enclosure assemblythat is covered by the vent featureso as to avoid obstructing the battery vent byproducts V during thermal runaway events. In this disclosure, the term “about” means that the expressed quantities or ranges need not be exact but may be approximated and/or larger or smaller, reflecting acceptable tolerances, conversion factors, measurement error, etc.